1. Field of the Invention
The present invention relates to an optical connector, and relates to an optical connector including a pair of housings accommodating an optical connector ferrule and detachably fitting each other, thereby, butt-jointing of ferrules is realized.
2. Description of Related Art
As a plug-in optical connector, there is a so-called backplane connector (hereinafter, also referred to as a backplane optical connector). The backplane optical connector has a structure such that a print board housing (hereinafter, also referred to as a PH housing) attached to a print board is fitted with a backplane housing (hereinafter, also referred to as a BH housing) attached to a backplane of a plug-in unit to assemble an optical connector adaptor which connects optical connectors (plugs).
The BH housing generally has a structure accommodating an internal housing into which a connector hole where a connector is fitted is penetrated inside an external housing having a square-tube shape and attached to the backplane (for example, see Japanese Unexamined Patent Application, First Publication No. H05-045541).
As a PH housing, a structure is used such that an insertion piece which is inserted into the BH housing and a claw elastic piece which is engaged with an internal housing of the BH housing are arranged and protruded at a base portion fixed on a print board.
Conventionally, a pair of insertion pieces is arranged with a gap in a direction perpendicular to an insertion and removal direction of the PH housing with respect to the BH housing (i.e., a width direction). In addition, a pair of claw elastic pieces is arranged with a gap in a longitudinal direction perpendicular to the insertion and removal direction and the width direction.
In the BH housing, the internal housing is provided movably with respect to the external housing in an axial direction (corresponding to the insertion and removal direction described above). In addition, at an inner surface of the external housing, a locking portion for locking a locking portion is protruded. Conventionally, a pair of locking portions is arranged with a gap in a direction perpendicular to an axial direction of the external housing (i.e., a width direction). On the other hand, at an internal housing, an elastic locking piece which is locked on a locking portion of the external housing is formed. Conventionally, a pair of elastic locking pieces is arranged with a gap in the width direction similar to the pair of locking portions of the external housing.
In a state where the elastic locking piece of the internal housing is engaged with the locking portion of the external housing, with respect to the external housing, the internal housing is prevented from moving to an insertion direction of the PH housing with respect to the BH housing (the direction corresponds to the axis direction described above).
An insertion piece accommodation hole into which the insertion piece of the PH housing is inserted is secured between the outer housing and the inner housing of the BH housing. The above-mentioned locking portion of the outer housing and the elastic locking piece of the inner housing are disposed in the insertion piece accommodation hole. In the related art, a pair of insertion piece accommodation holes is arranged with an interval therebetween in the horizontal width direction in the same manner as that of the pair of locking portions or the pair of elastic locking pieces.
In addition, an engagement convex portion which is engaged with a claw-attached elastic piece of the PH housing is formed in the inner housing of the BH housing. In the related art, a pair of engagement convex portions is formed on both pieces of the inner housing in the vertical width direction to correspond to a pair of claw-attached elastic pieces. Each of the engagement convex portions is formed to be recessed from the outside of the inner housing in the vertical width direction.
The PH housing is fitted to the BH housing by inserting the insertion piece into the insertion piece accommodation hole which is secured between the outer housing and the inner housing of the BH housing, and engaging the claw-attached elastic pieces which protrude from both sides of the base portion with the engagement convex portions of the inner housing of the BH housing.
In the backplane optical connector, by fitting the PH housing to the BH housing, the optical connector which is fitted into the connector hole that penetrates through the base portion of the PH housing and the optical connector which is fitted into the connector hole of the inner housing of the BH housing can be butt-jointed to each other.
In addition, by inserting the insertion piece of the PH housing into the insertion piece accommodation hole of the BH housing, the elastic locking piece of the inner housing is displaced inwardly and is thus released from a state of being locked to the locking portion of the outer housing. Accordingly, the inner housing can be moved with respect to the outer housing in the axis direction, and thus the optical connector on the PH housing side and the optical connector on the BH housing side are butt-jointed in an appropriate state.
In addition, the PH housing in a state of being fitted to the BH housing is pulled in a direction away from the BH housing so as to release the engagement of the claw-attached elastic piece with the inner housing of the BH housing, thereby being separated from the BH housing.
In the backplane optical connector of the related art, there is a need to secure gaps (the pair of insertion piece accommodation holes) into which the insertion pieces of the PH housing on both sides in the horizontal width direction are inserted, between the outer housing and the inner housing of the BH housing.
Therefore, in the backplane optical connector of the related art, there is a problem in that it is difficult to set the dimensions of the BH housing in the horizontal width direction to be small.